Telematic communication units (TCUs) include devices such as cellular phones (digital and analog), personal data assistants (PDAs), Global Positioning System (GPS) devices, and on-board Mobile Vehicle Communication Units (MVCUs). TCUs have made it possible for an entity to send and receive voice, data, and facsimile (FAX) communications from virtually anywhere on earth. Many passenger vehicles now incorporate an integrated communication system, such as an MVCU, providing a variety of fee-based subscription services in a mobile environment. The MVCU is typically a vehicle telematics device including a cellular radio, satellite transceiver, and/or global positioning capabilities. Communication through a carrier service may be initiated at the MVCU at turn-on or through manual or voice command phone number entry. Typically, a radio communication link is established between the MVCU and a call center through a wireless networkwireless network, using a node of the wireless network in the vicinity of the MVCU. In wireless telephone systems, a node is commonly referred to as a “wireless base station.” Once a radio communication link between the MVCU and the wireless base station has been established, the base station may utilize a combination of additional wireless stations, conventional telephone wire line networks, and possibly even satellite systems to connect the MVCU to the number to the call center.
During the course of normal communication loads, wireless network node(s) are typically more than capable of handling the volume of simultaneously established links. In some instances, however, the link volume may surge and/or the capacity of the network may be diminished so as to overburden wireless network node(s). As such, a transmission state between the MVCU and the wireless network node(s) may be compromised. Some on-going communications may be dropped and the establishment of novel connections may be prohibited. For example, a localized emergency may result in a sudden and short-lived burst in TCU communications, thereby saturating wireless network node(s) only temporarily. As a more extreme example, a wide-spread natural disaster (e.g., hurricane, earthquake, and the like) may result in a sudden and long-lived burst in TCU communications, thereby saturating wireless network node(s) indefinitely. To exacerbate the situation, the natural disaster may inhibit, cripple, or even destroy some of the wireless network components (e.g., nodes, lines, computers, power generators, etc.). In either case, vital communications may be hindered at a time when they are critically needed.
Vehicles having telematics functionality may include a multitude of sensors coupled to the MVCU as known in the art. Upon sensing a predetermined event, the MVCU may contact the control center. The events may range in seriousness from low oil or fuel levels, to a flat tire, to an emergency call or vehicle impact (i.e., ranging between non-emergency and emergency events). Some events may be detected automatically whereas some may be triggered, for example, by depressing an emergency button. As previously described, communications between the MVCU and the call center during the course of normal loads can be typically handled without incident. Should a portion of the wireless network become overburdened, certain events may not be communicated between the MVCU and the call center. Further, ongoing communication of so-called non-emergency events between the MVCU and the call center may preclude calls of a more serious nature from getting through. As such, it would be desirable to provide a strategy for prioritizing vehicle communications so as to allow more critical communications to be permitted.
It is an object of this invention, therefore, to provide a strategy for controlling vehicle communications during emergency situations, and to overcome the deficiencies and obstacles described above.